The secret society around the gorilla, which the Fong-Bulu (Ngui) is considered the god of fire, was last sought by the German ethnologist Günther Tessmann on an expedition in 1910 – in vain.

As the first and only outsider, Henning Christoph succeeded after long and extensive research in photographing the last ceremony of the covenant in the rainforests of Cameroon.

Despite language barriers and various conditions of secrecy, the talks with Chief Ngba of the Fong people from the village of Ngoazip revealed the following facts: The gorilla masks represent the ancestors of the Fong, who were pygmies.

The masks were made about 150 years ago and have been used in about 30 villages since then. The secret society was there to maintain tribal order and peace, which included the defense against witchcraft. Only the sons of chiefs could be initiated into the alliance when they reached the age of majority.

The calabashes attached to the back of many skulls served as poison containers from which presumed witches had to drink. If they were innocent, the poison could not harm them.